public class SellTicketsTester {
    public static void main(String[] args) {
        SellTickets s = new SellTickets();

        new Thread(s).start();
        new Thread(s).start();
        new Thread(s).start();
    }
}

class SellTickets implements Runnable {
    private int numOfTickets = 200;

    @Override
    public void run() {
        int count = 0;
        while (count <= numOfTickets) {
            System.out.println(Thread.currentThread().getName() + " is selling " + count++);
        }
    }
}
